The present invention relates to an artificial nipple used, for example, when an infant and the like are nursed. The present invention also relates to a feeding bottle having the artificial nipple.
Artificial nipples are generally attached to a container such as a feeding bottle housing, for example, milk housed therein, and are used for nursing infants and the like.
Conventional artificial nipples as such have a construction as shown in FIG. 14. FIG. 14 is a cross sectional view of a conventional artificial nipple 10.
As shown in the drawing, there is an artificial nipple 10 having a hollow portion A, through which, for example, milk housed in a container such as a feeding bottle, can flow. Also, the artificial nipple 10 is provided with a nipple portion 12, nipple body portion 11 and base portion 13, said portions being formed in such a manner as to cover the above mentioned hollow portion A. These portions are made of silicone rubber, isoprene rubber, and so on.
In addition, the nipple portion 12 is provided with an opening 12a, out of which milk, and the like, may be spouted out. Such an artificial nipple 10 is designed to be fitted to a container such as a feeding bottle. Then, milk, and the like, housed in a container such as a feeding bottle, are fed to the infant, via the artificial nipple 10. Here, the feeding bottle, and the like, is not shown in the drawings.
By the way, an infant 20, in fact, takes hold of the breast of, for example, his or her mother in his or her mouth to swallow or drink the milk. The movement of the infant 20 when holding the breast of, for example, his or her mother to swallow or drink the milk, the infant 20 moves his or her mouth by two steps roughly classified as follows: xe2x80x9cstep to prepare suckingxe2x80x9d and xe2x80x9cstep to start suckingxe2x80x9d. Each of the steps is explained as follows.
Step to Prepare Sucking
FIG. 15 is a view for describing the overview of the xe2x80x9cstep to prepare suckingxe2x80x9d.
As shown in the FIG. 15, when an infant 20 holds the breast 30 of his or her mother, and so on, in the mouth, the infant largely opens his or her upper and lower lips 27a, 27b. Then, the infant extends his or her tongue 23 over the lower tooth bank 28b, resulting in a condition where the tongue touches the lower lip 27b. 
Then, the infant holds the breast in his or her mouth. At that time, the infant 20 largely opens his or her upper and lower lips 27a, 27b. The upper and lower lips 27a, 27b are very soft and easily transformed as shown in FIG. 15. Therefore, when the infant tightly contacts the upper and lower lips 27a, 27b at the breast 30, in particular, a breast circle 31, they 27a, 27b are opened in such a manner as to naturally roll them up or down in the vertical direction of the drawing.
In addition, an infant 20 transforms his or her tongue 23 to transport the tip 32a of the nipple of mother, and the like, into the deepest point of his or her mouth roof cavity 22. The movement that an infant 20 extends his or her tongue to transport the tip 32a of the nipple into his or her mouth roof cavity 22, as stated here, is generally referred to as xe2x80x9cthe first elongation.xe2x80x9d
The nipple 32, in a condition of xe2x80x9cthe first elongationxe2x80x9d described above, is compressed, by tongue 23, against his or her upper palate 21, upper tooth bank 28a and upper lip 27a, as shown in FIG. 15. At that time, the whole of the nipple 32 is also surrounded by the inside of his or her cheeks and the tongue 23.
In particular, the tongue 23, surrounding the nipple 32, transforms for holding the nipple 32 completely. The nipple 32 is a non-hollow organization. When the nipple 32 is transformed, the mother""s milk is transferred to the tip 32a thereof without the nipple 32 being terminally crushed.
As stated above, the xe2x80x9cstep to prepare suckingxe2x80x9d is finished.
Step to Start Sucking
Then, the xe2x80x9cstep to start suckingxe2x80x9d will be explained. First of all, the infant moves his or her tongue 23 in a peristaltic manner, at the stage of xe2x80x9cstep to start suckingxe2x80x9d.
In other words, the infant stimulates the breast 30, areola 31 and nipple 32 to promote his or her mother to secrete mother""s milk as well as to transfer the mother""s milk up to the tip of the nipple 32. Here, the tongue 23 moves in such a manner that an expansion of the tongue 23 continuously moves from the tip portion of the tongue to the root portion thereof. Then, such expansion further moves to a portion of the tongue just beyond the tip 32a of the nipple followed by transferring to a deep portion of the mouth.
Such movement of the expansion is shown in FIGS. 16 (a) to (c). FIGS. 16 (a) to (c) show magnified views for describing the overview, in relation between the tongue 23 and the tip 32a of the nipple, showing a sequence of the peristaltic movement where the expansion of the tongue 23 just goes beyond the tip 32a of the nipple and further goes to the deep portion of the mouth.
Thus, the nipple 32 is elongated by the transferring of the expansion of the tongue 23, from the tip thereof to the root thereof. Also, the tip 32a of the nipple is a non-hollow organization, and the nipple may be extended in the direction of the tip thereof, while the nipple is deformed in a slightly crushed manner as shown in FIG. 16(a). As shown in FIG. 16(b), when the expansion of the tongue 23 moves in a peristaltic manner, the nipple 32 is extended just before mother""s milk spouts out.
The step stated here is referred to as the xe2x80x9csecond elongation,xe2x80x9d which is distinguished from the xe2x80x9cfirst elongationxe2x80x9d as mentioned above. Thus, the xe2x80x9csecond elongationxe2x80x9d starts when the tongue 23 moves the expansion, beginning at the tip of the tongue.
Next, there comes a step in which the mother""s milk is squirted out. Generally, the infant transforms the tongue 23 to move the expansion so as to draw the nipple of mother, and the like, toward the tip 32a of the nipple. Then, the expansion of the tongue 23 moving in a peristaltic manner reaches at the tip portion of the tip 32a, so as to form a sealed space E surrounded by the tip 32a of the nipple, the expanded tongue 23, an inner part of the mouth roof cavity 22, and the soft palate 24 located inside the mouth roof cavity 22.
Then, the tongue 23 contacts the soft palate 24, during which the movement in a peristaltic manner further continues to transfer the expansion of the tongue 23 into the deeper portion of the mouth. Then, as shown FIG. 16 (b), the capacity of the sealed space E increases or grows, and thereby, a decreased pressure is generated inside the sealed space E.
When there is formed a sealed space having a decreased pressure as such, the tip 32a of the nipple is drawn into the sealed and decreased pressure space E, resulting in further elongating the tip 32a of the nipple. When the elongation as such is accomplished, the xe2x80x9csecond elongationxe2x80x9d is finished.
By moving the tongue 23 in a peristaltic manner resulting in generating the decreased pressure, the mother""s milk, gathering at the tip 32a of the nipple, spouts out into the mouth of the infant 20. Then, the infant 20 releases the tongue 23 from the soft palate 24 and opens the sealed space E, and then, the infant 20 may swallow or drink the mother""s milk that has been squirted out, as shown in FIG. 16 (c).
After the xe2x80x9cfirst elongationxe2x80x9d is finished, the infant 20 repeats the xe2x80x9csecond elongationxe2x80x9d in a rapid cycle of once per 0.7 seconds, so as to drink the mother""s milk of, for example, his or her mother, as stated above.
When the mother, and so on, breast-feeds an infant 20, the infant 20 drinks the mother""s milk in the manner as described above, via the nipple of his or her mother, and so on. Similarly, when formula of artificial milk that is not the mother""s milk is fed to the infant 20, the infant 20 takes the same sucking behavior as described above. Therefore, an artificial nipple 10 imitates the appearance of the mother""s nipple as shown in FIG. 14, and is installed on a feeding bottle so as to nurse an infant 20.
The nipple part 12 of the conventional artificial nipple 10, as shown in the FIG. 14, has a length, in the horizontal direction in FIG. 14, longer than that of the nipple of mother, and the like. This is because the artificial nipple 10 is, in advance, designed to correspond to the length in a condition of the xe2x80x9cfirst elongationxe2x80x9d in the course of the xe2x80x9cstep to prepare suckingxe2x80x9d as mentioned above, shown in FIG. 15.
However, such a nipple portion 12 of the conventional artificial nipple 10, as shown in FIG. 14, has some of the following problems.
That is, an infant 20, at the xe2x80x9cstep to prepare suckingxe2x80x9d as mentioned above, holds the artificial nipple 10 in his or her mouth, and then, he or she transforms the nipple portion 12 by using his or her tongue 23 so as to place the tip of the nipple portion 12 at the deepest point in the mouth roof cavity 22, as shown in FIG. 16.
However, the artificial nipple 10 may sometimes be insufficient in elasticity, so that an infant, and so on, may find it difficult to transform up the tip of the nipple portion by the tongue 23, resulting in a situation in which the infant 20 may not move the tongue 23 in a peristaltic manner nor form a sealed space E as shown in FIG. 16(a). Further, when an artificial nipple 10 is hard, it is difficult for an infant to smoothly move the tongue 23 in a peristaltic manner. Furthermore, if the nipple portion 12 is hard, the nipple portion 12 may not be transformable in an upward or downward direction, in terms of deformation, resulting in a situation in which it is difficult to form the sealed space E.
Further, even if an infant 20 moves his or her tongue 23 in a peristaltic manner, it may be difficult to transform the nipple portion 12 of the artificial nipple 10, in accordance with the above mentioned xe2x80x9csecond elongationxe2x80x9d as shown in FIG. 16 (a), resulting in difficulty in obtaining the sealed space E. Accordingly, it may be difficult to generate a decreased pressure in the sealed space E even if transferring the expansion of the tongue 23, and thereby, it is difficult for the infant 20 to swallow or drink formula, since the formula, gathered near the tip of the nipple portion 12, is difficult to spout out.
In solving the above-mentioned problems, there may be an alternative way to make an artificial nipple 10 made of a soft material. Such alternative way focuses on an improvement of a condition where an infant holds the artificial nipple 10 in his or her mouth to locate it in the mouth roof cavity 22, or where it makes easy to transform the nipple portion at the second elongation. However, such alternative way will cause another problems that when an infant 20 moves his or her tongue 23 in a peristaltic manner as described above, the nipple portion, made of soft material, may be completely deformed so as to clog the inner space A. Accordingly, it will be difficult for the formula, and the like, to flow to the opening 12a of the nipple portion 12, and thereby, the infant 20 will have difficulty in drinking or swallowing formula and the like.
Furthermore, in addition to the difficulties as stated above, if such an artificial nipple 10 is continuously used by an infant 20 and the infant 20 becomes accustomed to move his or her mouth, he or she may acquire a skill of drinking the formula, and the like, even from such artificial nipple. However, such an ability will adversely affect and confuse the infant when he or she is breast-fed by the nipple of his or her mother, and the like.
Accordingly, there are objectives of the present invention, in consideration of the above-mentioned problems. That is, it is necessary to provide an artificial nipple, which may be transformed and elongated appropriately when an infant moves his or her tongue in a peristaltic manner, such that it behaves in the same manner as the nipple of the mother, and so on. Also, there is an objective to provide an artificial nipple that does not squirt out liquid in an inferior manner, due to deforming the artificial nipple and intermittently interrupting the flowing path. Also, there is an objective to provide a feeding bottle provided with the artificial nipple according to the present invention.